Wikipedia defines the terms ‘Perpetual Calendar’ as a calendar valid for many years, usually designed to look up the day of the week for a given date in the future. For those who do not know, the perpetual calendar is one of the most prized and coveted complications that Haute Horlogerie has ever seen.
The Story Behind The Perpetual Calendar
When talking about calendars and the various mechanisms of time, perhaps the most intriguing one is the leap year. Why does it exist? Who invented it? Why do we even need it? Well, in order to not digress too much I’ll keep it short. I will keep it informative though. The calendar we use today is called the Gregorian Calendar. But that only same into existence in 1582. Prior to that people followed the Julian calendar.
The calendar was simply divided into 365 days, 12 months with 30/31 days with a 28-dat February, and a 24-hour day. However, there was one slight miscalculation. The calendar years was still shorter than the solar year, that is, the time it takes the Earth to complete one revolution.
The solar year is also a wild concept but I did my research. It comprises of 365 days, 5 hours, 49 minutes, and 16 seconds in case you were wondering. This is where Pope Gregory VIII comes into the picture. He added an extra day in the month February every four years calling it the ‘leap day’ and that particular year the ‘leap year’. Every 100 years, this extra day is left out but every 400 years, it is added back on. This is done as a measure to balance out the overage caused due to the extra day.
Perpetual Calendar – The Complication
This brings us to the complication we love so much, the perpetual calendar. Now that you understand how crazy complicated the concept of the leap year is, you can comprehend how difficult it must be to create a mechanism that takes into account the date, days, months, years, the 30-31 cycle, the 28 days of February, the extra day every four years, every 100th year without the leap day, every 400th year with the leap day, and so on. In 1762, English watchmaker named Thomas Mudge did exactly that. He did the impossible and created the perpetual calendar complication in a pocket watch.
In 2016, that watch went up for auction and was bought up by none other than Patek Phillipe. It was poetry in real life as there is no other brand that can do justice to a perpetual calendar like Patek Phillipe can. As it happens to be, Patek Phillipe was the first horologist to create the very first wristwatch with a perpetual calendar in 1925, the first wristwatch with a retrograde perpetual calendar in 1937, and the first wristwatch series of perpetual calendars in 1941. This series had the iconic reference number 1526. It’s as if the brand came a full circle.
Oh, and it was also the first one to create a perpetual calendar with a self-winding movement in 1962 with the legendary reference number 3448 and the first to create a perpetual calendar chronograph in 1941. It took another Swiss watchmaker about 16 years before it could match this mean feat (self-winding perpetual calendar).
There is, however, another watch manufacturer that takes pride in its conquests over the perpetual calendar. As many of you must have already figured it out, it is none other than Audemars Piguet.
Audemars Piguet and The Perpetual Calendar
Bold, rebellious, and iconoclastic, these are the words that best describe Audemars Piguet’s perpetual calendar watches. Audemars Piguet is a game changer and a trailblazer in the game. As far as Swiss high horology is concerned, Audemars Piguet is that rare gem that always comes up with something unexpected.
Now, the watch that everybody talks about when the name Audemars Piguet comes up is the Royal Oak. But we will be strictly sticking to the perpetual calendar range of watches from the Swiss horologist. The tale begins in 1875 with Jules Louis Audemars, who had to create a school watch in order to graduate from watchmaking school.
This watch had dead seconds, as in the second that only proceeded at each second instead of incrementally. And yes, the watch also possessed a perpetual calendar. The genius of this watch could not me emphasised enough. A closer look at the timepiece below and you will notice that the 12 o’clock marker had a sub-dial with full fledged leap year cycle.
This was the old-school way of making pocket watches with perpetual calendars. A key distinction here is that Jules Audemars chose to show the leap year. This is something that was consistently omitted from watches. A great example would be the watch that Patek Phillipe pocket watch that was made for the popular American automobile maker, James Ward. The watch is referenced below. In order to align these pocket watches as per the leap year, they were sent to watchmakers who would remove the dial to set the calendar.
The First Perpetual Calendar Wristwatch With a Leap-Year Display – Reference 5516
There were a total of 12 piece made of the Ref. 5516, three of which were termed as the Pre-Series as they did not have the leap-year indicators. The first one was created in 1947 as he worked on a 14-ligne perpetual calendar and adapted it to the Calibre 13VZSS.
The second example was made in 1948. The watch has a much more expressive and it has a case that was much more stylised. Look carefully at the perimeter of the case and you will see that date display. The central hand was responsible for indicating the date. The watch had a moon phase at 12 o’clock and still no indication of the leap-year.
The Official Ref. 5516 Series
The first official Audemars Piguet Ref. 5516 was unveiled in the year 1955. There were a total of three pieces made and all of them were simply outstanding. They resembled the 1875 model created by Jules Audemars as they displayed a full 48-month leap-year cycle. The magnitude of skill and finesse displayed in this reference was outright ridiculous. This was perhaps the most beautiful watch made in that era. The attention to details was so accurate and persistent that it was like visualising poetry in motion.
The date display resembled the 1948 Pre-Series model. A central hand pointed towards the date marked on the perimeter of the dial. The 12 o’clock position was occupied by a moon phase. The month was actually shown twice. One was the much cleaner and uncluttered 3 o’clock sub-dial and the second was the rather complicated 6 o’clock sub-dial. The sub-dial at the 9 o’clock position displayed the day of the week.